Washington ? New Mexico Gov. Bill Richardson intends to take the initial step toward the Democratic nomination, hoping his extensive resume will fuel a campaign to become the first Hispanic president.

Richardson plans to announce Sunday that he will soon file the papers to create a presidential exploratory committee, several officials with knowledge of his plans said Friday. The governor is scheduled to appear on ABC’s “This Week.”

His entry would make the Democratic race the most diverse presidential contest in history. Besides Richardson’s bid to be the first Hispanic chief executive, Sen. Barack Obama would be the first black president and likely candidate Sen. Hillary Rodham Clinton would be the first female president.

Richardson, 59, is a former congressman, U.N. ambassador and Energy Department secretary. He brings a wealth of experience in international affairs that has extended even into his governorship of a small but important swing state.

He has hosted talks on North Korea’s nuclear program in New Mexico and most recently traveled to Sudan to meet with the country’s president to press him for an end to the bloodshed in Darfur.

Despite having one of the most varied and impressive portfolios in politics, Richardson enters the race as an underdog. Polling in early voting states shows him ranking near the bottom in a very crowded Democratic field led by Clinton, Obama and 2004 vice presidential nominee John Edwards.

Richardson does not have the national fundraising network of some of his rivals in what is bound to be a very expensive race. And he’ll have to spend the next two months concentrating on a legislative session in Santa Fe instead of campaigning.

But Richardson’s decision to form an exploratory committee will allow him to begin raising money and putting together his campaign organization. A decision on whether to formally enter the race is expected in the spring.

On Friday, Richardson ended a talk to the Greater Albuquerque Chamber of Commerce by responding to an audience member’s prodding for him to announce his plans.

He grinned and said: “Number one, the announcement will be made in New Mexico. Number two, I said I would do it before the end of January – I will stick with that. And number three … regardless of any announcement, my main priority is being governor (and) the legislative session.”

“Now, anything more,” he said. “Tune in.”

His office had no additional comment.